The present invention relates to an improved canister for containing gas-treating material such as a desiccant or oxygen absorber.
By way of background, there are in use canisters of various types for adsorbing moisture from pharmaceutical containers and for treating environments by absorbing gases therefrom. One type of prior canister is disclosed in U.S. Pat. No. 4,772,300 wherein a web-bonded polyethylene is secured to the ends of a polyethylene body by means of ultrasonic welding. However, there was no consistency in obtaining good uniform welds therebetween. It is believed that the deficiency was due to the fact that the interface of both parts did not melt at the same time to create a good fused bond.